System and method for regenerating a diesel particulate filter

ABSTRACT

A system for regenerating a diesel particulate filter of the present invention includes a fixing part, a fluid supplying part, a fluid inhaling part, and a controller. The fixing part fixes a housing of a diesel oxidation catalyst-diesel particulate filter assembly. The fluid supplying part supplies a fluid of high temperature and high pressure to a rear end of the housing. The fluid inhaling part inhales the fluid from a space between the diesel oxidation catalyst and the diesel particulate filter of the housing. The controller controls the fluid supplying part such that temperature of the fluid between the diesel oxidation catalyst and the diesel particulate filter arrives at a first predetermined temperature.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean Patent Application No. 10-2005-0122774 filed in the Korean Intellectual Property Office on Dec. 13, 2005, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present invention relates to a diesel oxidation catalyst (DOC)-diesel particulate filter (DPF) assembly, and in particular, to a system and a method for generating a diesel particulate filter.

(b) Description of the Related Art

In general, a DOC-DPF assembly includes a housing, a diesel oxidation catalyst, and a diesel particulate filter, and the diesel oxidation catalyst and the diesel particulate filter are sequentially mounted in the housing with respect to an exhaust direction. Such a DOC-DPF assembly is mounted in an exhaust system of a diesel engine so as to remove air pollution material exhausting from the diesel engine.

The diesel oxidation catalyst reduces particulate matter (PM) and removes gaseous noxious materials associated with the PM, such as carbon monoxide (CO), hydrocarbons (HC), aldehydes, and polycyclic aromatic hydrocarbons (PAH).

The diesel particulate filter removes the PM such dry soot and nitric oxide (NO) which are not removed in the diesel oxidation catalyst.

In addition, if the PM is excessively deposited on the diesel particulate filter, engine efficiency may be reduced since the exhaust system does not operate at full performance. Therefore, in order to increase the engine efficiency, the PM deposited on the diesel particulate filter must be removed.

In order to remove such PM, it is burned using high temperature exhaust gas. Furthermore, in order to increase the temperature of the exhaust gas, additional fuel is injected into the combustion chamber, and consequently the engine speed increases.

However, if the PM is excessively deposited on the diesel particulate filter, the engine speed may not be increased since the exhaust backpressure is excessively increased. As a result, since the PM is not burned, the expensive DOC-DPF assembly becomes ineffectual so it must be replaced.

The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

SUMMARY OF THE INVENTION

The present invention has been made in an effort to provide a system and a method for regenerating a diesel particulate filter having advantages of enabling reuse of the diesel particulate filter.

A system for regenerating a diesel particulate filter according to an embodiment of the present invention includes a fixing part for fixing a housing of a diesel oxidation catalyst-diesel particulate filter assembly; a fluid supplying part for supplying a fluid of a high temperature and high pressure to a rear end of the housing; a fluid intake part for taking in the fluid from a space between the diesel oxidation catalyst and the diesel particulate filter of the housing; and a controller for controlling the fluid supplying part such that the temperature of the fluid between the diesel oxidation catalyst and the diesel particulate filter arrives at a first predetermined temperature.

In a further embodiment, the fluid supplying part includes a first pipe that is connected to a pre-existing first outlet at the rear of the housing; a burner that is disposed on the first pipe so as to increase the temperature of the fluid; and a turbine that is disposed on the first pipe so as to discharge the fluid to the diesel particulate filter.

In a further embodiment, the fluid intake part includes a second outlet that is formed at a first portion between the diesel oxidation catalyst and the diesel particulate filter of the housing; a second pipe that is connected to the second outlet; a pump that is disposed on the second pipe so as to take in the fluid passing through the diesel particulate filter; and an accumulation unit that is disposed on a rear end of the second pipe so as to accumulate the fluid.

In a further embodiment, the system for regenerating a diesel particulate filter according to an embodiment of the present invention further includes a first plug for opening and closing a pre-existing inlet at a front end of the housing.

In a further embodiment, the fluid intake part further includes a second plug for opening and closing the second outlet.

In a further embodiment, the system for regenerating a diesel particulate filter according to an embodiment of the present invention also includes a first temperature sensor that is disposed at a second portion between the diesel oxidation catalyst and the diesel particulate filter of the housing.

In a further embodiment, the controller operates the pump, the turbine, and the burner, and stops the burner if a temperature being measured by the first temperature sensor arrives at the first predetermined temperature. In a further embodiment, the system for regenerating a diesel particulate filter according to an embodiment of the present invention further includes a second temperature sensor that is disposed on the first pipe close to the first outlet, wherein the controller further includes repeatedly operating/stopping the burner on the basis of a second predetermined temperature such that a temperature at the second temperature sensor is the second predetermined temperature, until the temperature at the first temperature sensor arrives at the first predetermined temperature.

A method for regenerating a diesel particulate filter according to an embodiment of the present invention includes removing a diesel oxidation catalyst-diesel particulate filter assembly from an exhaust system; fixing the assembly to a fixing part; closing an inlet of the assembly, opening a second outlet of the assembly, and connecting a second pipe to the second outlet; connecting a first pipe to a first outlet of the assembly; operating a pump, a turbine, and a burner; determining whether a temperature being measured by the first temperature sensor reaches a first predetermined temperature; and stopping the pump, the turbine, and the burner, if the first predetermined temperature is reached.

In a further embodiment, the method for regenerating a diesel particulate filter according to an embodiment of the present invention further includes repeatedly operating/stopping the burner on the basis of a second predetermined temperature such that the temperature at the second temperature sensor is the second predetermined temperature, until the temperature at the first temperature sensor arrives at the first predetermined temperature.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view showing a system for regenerating a diesel particulate filter according to an exemplary embodiment of the present invention.

FIG. 2 is block diagram showing a controller and elements connected to the controller, in a system for regenerating a diesel particulate filter according to an exemplary embodiment of the present invention.

DESCRIPTION OF REFERENCE NUMERALS INDICATING PRIMARY ELEMENTS IN THE DRAWINGS 100: fixing part 300: fluid supplying part 310: first pipe 330: burner 350: turbine 500: fluid intake part 510: second outlet 530: second pipe 550: pump 570: accumulation unit 700: controller 810: first temperature sensor 820: second temperature sensor

DETAILED DESCRIPTION OF THE EMBODIMENTS

With reference to the accompanying drawings, the present invention will be described in order for those skilled in the art to be able to implement the invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

FIG. 1 is a schematic view showing a system for regenerating a diesel particulate filter according to an exemplary embodiment of the present invention. FIG. 2 is block diagram showing a controller and elements connected to the controller, in a system for regenerating a diesel particulate filter according to an exemplary embodiment of the present invention.

A system for regenerating a diesel particulate filter according to an exemplary embodiment of the present invention, as shown in FIGS. 1 and 2, includes a fixing part 100, a fluid supplying part 300, a fluid intake part 500, and a controller 700.

The fixing part 100 fixes a housing 20 of a diesel oxidation catalyst-diesel particulate filter assembly 10 (hereinafter called as “DOC-DPF assembly”) such that the housing 20 does not move.

The fluid supplying part 300 supplies a fluid at a high temperature and high pressure to a rear end of the housing 20.

The fluid intake part 500 takes in the fluid from a space between the diesel oxidation catalyst 30 and the diesel particulate filter 40 of the housing 20.

The controller 700 controls the fluid supplying part 300 such that the temperature of the fluid between the diesel oxidation catalyst 30 and a diesel particulate filter 40 arrives at a first predetermined temperature. Therefore, particulate matter (hereinafter called “PM”) deposited on the diesel particulate filter 40 is dissolved by the high temperature fluid supplied from the fluid supplying part 300, the PM is separated from the diesel particulate filter 40 by the high pressure fluid, and the PM moves to the fluid intake part 500 by a suction force of the fluid intake part 500. In addition, since the fluid supplied from the fluid supplying part 300 has the high pressure, other foreign materials (e.g., ash etc.) in addition to the PM deposited on the diesel particulate filter 40 are also removed. Further, since the temperature of the fluid can be optimally controlled by the controller 700, other elements of the system can be prevented from being degraded by heat.

The fluid supplying part 300 will hereinafter be described in detail.

The fluid supplying part 300 may include a first pipe 310, a burner 330, and a turbine 350.

In more detail, the first pipe 310 is connected to a pre-existing first outlet 21 at the rear of the housing 20. The burner 330 is disposed on the first pipe 310, and it increases the temperature of the fluid. The turbine 350 is diposed on the first pipe, and it rotates so as to discharge the fluid to the diesel particulate filter 40. Furthermore, the fluid supplying part 300 may include a fan 370 that is disposed on a front end of the burner 350 with respect to the flow direction so as to smoothly supply the fluid thereto.

The fluid intake part 500 will be hereinafter described in detail.

The fluid intake part 500 may include a second outlet 510, a second pipe 530, a pump 550, and an accumulation unit 570.

In more detail, the second outlet 510 is formed at a first portion between a diesel oxidation catalyst 30 and the diesel particulate filter 40 of the housing 20. The second pipe 530 is connected to the second outlet 510. The pump 550 is disposed on the second pipe 530 so as to smoothly take in the fluid passing through the diesel particulate filter 40. The accumulation unit 570 is disposed on a rear end of the second pipe 530 so as to accumulate the fluid.

In addition, the system for regenerating a diesel particulate filter according to an exemplary embodiment of the present invention, as shown in FIG. 1, may further include a first plug 200 for opening and closing a pre-existing inlet 22 at a front end of the housing 20.

Therefore, the first plug 200 can prevent the high temperature fluid from inflowing to the diesel oxidation catalyst 30.

In addition, the fluid intake part 500 may further include a second plug 400 for opening and closing the second outlet 510.

Therefore, when the exhaust system (not shown) of a vehicle is operated after the DOC-DPF assembly 10 is mounted on the exhaust system, the second plug can prevent exhaust gas from being discharged from the second outlet 510.

In addition, the system for regenerating a diesel particulate filter according to an exemplary embodiment of the present invention, as shown in FIG. 1, may further include a first temperature sensor 810.

In more detail, the first temperature sensor 810 is disposed at a second portion between the diesel oxidation catalyst 30 and the diesel particulate filter 40 of the housing 20 so as to detect a temperature therebetween.

In addition, the fluid supplying part 300 may further include a second temperature sensor 820 that is disposed on the first pipe 310 close to the first outlet 21, so as to prevent the turbine 350 from being degraded by heat. Further, since the fluid heated by the burner 330 passes through the diesel particulate filter 40, the temperature of the space between the diesel oxidation catalyst 30 and the diesel particulate filter 40 must not be rapidly increased. In order to increase the temperature of the fluid between the diesel oxidation catalyst 30 and the diesel particulate filter 40 up to the first predetermined temperature, the burner 330 generates a substantial amount of heat. As a result, the turbine 350 and the diesel particulate filter 40 may be rapidly expanded due to the substantial heat of the burner 330, and be broken. However, if temperature at the first pipe 310 is firstly controlled by the second temperature sensor 820 and the controller 700, the breaking of the turbine 350 and the diesel particulate filter 40 can be prevented.

Here, the first predetermined temperature may be about 800° C., and the second predetermined temperature may be about 600° C. to 650° C.: In particular, the first predetermined temperature is higher than the second predetermined temperature because of an exothermic reaction of the diesel oxidation catalyst 30.

The controller 700 will hereinafter be described in detail.

The controller 700 can be realized by one or more processors activated by a predetermined program.

The controller 700 operates the pump 550, the turbine 350, and the burner 330, and it stops the burner 330 if the temperature being measured by the first temperature sensor 810 arrives at the first predetermined temperature.

In addition, the controller 700 may repeatedly operate/stop the burner 330 on the basis of the second predetermined temperature, such that the temperature at the second temperature sensor 820 is maintained at the second predetermined temperature until the temperature at the first temperature sensor 810 arrives at the first predetermined temperature. Therefore, if the temperature at the first pipe 310 is controlled to the second predetermined temperature by the second temperature sensor 820 and the controller 700, as mentioned above, the turbine 350 and the diesel particulate filter 40 can be prevented from being broken.

A method for regenerating a diesel particulate filter according to an exemplary embodiment of the present invention will be hereinafter described in detail.

First, in a case that the DOC-DPF assembly 10 must be regenerated, the DOC-DPF assembly 10 is removed from the exhaust system (not shown) and is fixed to the fixing part 100.

Thereafter, the inlet 22 of the DOC-DPF assembly 10 is closed by the first plug 200, the second outlet 510 the DOC-DPF assembly 10 is opened so as to connect the second pipe 530 thereto, and the first pipe 310 is connected to the first outlet 21 of the DOC-DPF assembly 10.

In addition, the pump 550, the turbine 350, and the burner 330 are operated by the controller 700.

During the regeneration, the controller 700 determines whether the temperature being measuring by the first temperature sensor 810 reaches the first predetermined temperature (about 800° C.). In more detail, the controller 700 repeatedly operates and stops the burner on the basis of the second predetermined temperature such that the temperature at the second temperature sensor 820 is the second predetermined temperature (about 650° C. to 700° C.) until the temperature at the first temperature sensor 810 arrives at the first predetermined temperature. That is, the controller 700 stops the burner 330 if the temperature at the second temperature sensor 820 is higher than the second predetermined temperature, and it operates the burner 330 if the temperature at the second temperature sensor 820 is lower than the second predetermined temperature. Such operating and stopping of the burner 330 are repeatedly performed until the temperature at the first temperature sensor 810 arrives at the first predetermined temperature.

The controller 700 stops the pump 550, the turbine 350, and the burner 330 when the temperature at the first temperature sensor 810 arrives at the first predetermined temperature. The temperature and pressure of the DOC-DPF assembly 10 are then allowed to slowly reduce. A time for the temperature and the pressure to return to a normal state may be about 5 to 10 minutes.

As has been explained, the system and method for regenerating a diesel particulate filter according to an exemplary embodiment of the present invention may have the following advantage.

According to the embodiment of the present invention, an expensive diesel particulate filter can be reused.

While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. 

1. A system for regenerating a diesel particulate filter, comprising: a fixing part for fixing a housing of a diesel oxidation catalyst-diesel particulate filter assembly; a fluid supplying part for supplying a fluid of a high temperature and high pressure to a rear end of the housing; a fluid intake part for taking in the fluid from a space between the diesel oxidation catalyst and the diesel particulate filter of the housing; and a controller for controlling the fluid supplying part such that the temperature of the fluid between the diesel oxidation catalyst and the diesel particulate filter arrives at a first predetermined temperature.
 2. The system of claim 1, wherein the fluid supplying part comprises: a first pipe that is connected to a pre-existing first outlet at the rear of the housing; a burner that is disposed on the first pipe so as to increase the temperature of the fluid; and a turbine that is disposed on the first pipe so as to discharge the fluid to the diesel particulate filter.
 3. The system of claim 2, wherein the fluid intake part comprises: a second outlet that is formed at a first portion between the diesel oxidation catalyst and the diesel particulate filter of the housing; a second pipe that is connected to the second outlet; a pump that is disposed on the second pipe so as to take in the fluid passing through the diesel particulate filter; and an accumulation unit part that is disposed on a rear end of the second pipe so as to accumulate the fluid.
 4. The system of claim 1, further comprising a first plug for opening and closing a pre-existing inlet at affront end of the housing.
 5. The system of claim 3, wherein the fluid intake part further comprises a second plug for opening and closing the second outlet.
 6. The system of claim 3, further comprising a first temperature sensor that is disposed at a second portion between the diesel oxidation catalyst and the diesel particulate filter of the housing.
 7. The system of claim 6, wherein the controller: operates the pump, the turbine, and the burner; and stops the burner if a temperature being measured by the first temperature sensor arrives at the first predetermined temperature.
 8. The system of claim 7, further comprising a second temperature sensor that is disposed on the first pipe close to the first outlet, wherein the controller repeatedly operates/stops the burner on the basis of the second predetermined temperature such that the temperature at the second temperature sensor is the second predetermined temperature, until the temperature at the first temperature sensor arrives at the first predetermined temperature.
 9. A method for regenerating a diesel particulate filter, comprising: removing a diesel oxidation catalyst-diesel particulate filter assembly from an exhaust system; fixing the assembly to a fixing part; closing an inlet of the assembly, opening a second outlet of the assembly, and connecting a second pipe to the second outlet; connecting a first pipe to a first outlet of the assembly; operating a pump, a turbine, and a burner; determining whether a temperature being measured by a first temperature sensor reaches a first predetermined temperature; and stopping the pump, the turbine, and the burner if the first predetermined is reached.
 10. The method of claim 9, further comprising repeatedly operating/stopping the burner on the basis of a second predetermined temperature such that the temperature at a second temperature sensor is the second predetermined temperature, until the temperature at the first temperature sensor arrives at the first predetermined temperature. 